Telephone installation



Sept. 9 1924. 1,507,668

E. A. DRISCOLL TELEPHONE INSTALLATION Filed June 1s 1921 s sh uu-smn. 1

Edward aiflrsogll, W k'ag E. A. DRISCOLL kpto 9 g TELEPHONE INSTALLATION Filed June 15 192; 3 shits-Sheet. 2

zwwrzJJrasM I 13 0 1% X Filed June 15, 1921 3 Sheets-Sheet 5 awwentozr Patented Sept. 9, 1924.

UNITED STATES EDWARD A. DRISCOLL, OF NEW YORK, N. Y.

TELEPHONE INSTALLATION.

Application filed June 15, 1921.

To all whom it may concern:

Be it known that I, EDWARD A. DRIscoLL, a citizen of the United States, and a resident of the borough of Manhattan, city, county, and State of New York, have invented certain new and useful Improvements in Telephone Installations, of which the following is a specification.

My improvements relate to the installation of telephones generally, but especially to those of the so called desk and wall type, my main objects being to obviate complication of initial structure and difiiculties heretofore incidental to the maintenance in operative condition of such installations; and also to render the same more simple, inexpensive, and effective by eliminating parts and details of construction heretofore deemed indispensable.

To this end my invention consists essentially in the novelmethod and means of electrically connecting up the several parts and appliances essential to installation of a telephone receiver and transmitter substantially as herein described and claimed specifically'a distinctive feature being my method of attaining the desired results by the use of a single pair of make and break contact points in conjunction with my novel electric circuit system, all as hereinafter fully set forth.

In the accompanying drawings,

Fig. 1, is a diagrammatic representation of my improved method of installation as applied to a so called desk telephone outfit;

Fig. 2, is a similar representation of my method of installation as applied to a wall or box telephone outfit;

Fig. 3, is a diagram of the electric circuits involved in method of telephone installation;

Fig. 4, is a front elevation of the two contact points used in my system of installa- Serial No. 477,644.

by the wire 07. The induction coil I has two pof windings, namely, a primar winding low resistance and a secon ary win of higher resistance.

The receiver R, is interposed in the line 1", 1", which connects the contact is, with the primary winding p, of the induction coil I, and with the secondary coil 8, thereof, through the bridge wire or jumper j, the said secondary Wmding s, of the induction coil I, being connected by the line 8', with the post a, of the main line L.

The transmitter T, is connected through the wire t, with the primary winding 1), and the secondary winding 8, of the induction coil I, though the wire t, which also connects with the aforesaid Wire 8', between the secondary winding 8, and the post a, of the main line.

The bell circuit 6, b, in which the condenser C, is interposed, connects with the main line binding posts a a, and is operated in the usual manner y an alternating current, whereas the transmitter and receiver circuits are energized by direct current derived from said line wires L, L, in a manner Well known in the art,-the main novelty in the present case being s ecifically the simplified method of installation herein set forth, and exemplified particularly and diagrammatically in Fig. 3 of the drawings,

whereby a maximum degree'of efliciency. is attained by a minimum of parts and-connections controlled by a single pair of contacts k is. 1 l

The mounting of the latter is preferably effected by means of the duplex bushing shown in detail in F i s. 4 and 5, which insures perfect insulation for the contacts k, [6, ins. simple but effective manner.

The circuit Wiring above described, and shown more particularly in Figure 3, is peculiarly adapted for the various purposes contemplated by my invention, and particularly for rendering possible the elimination of a considerable number of working parts, as herein described.

By my improved method of circuit wiring I am enabled to include the induction coil I, in the casingof a desk telephone as well as to include the said induction coil I, as heretofore, in a wall casing, sothat the essential parts of both desk and wall telephone systems may be protected and ena closed in metallic boxes or encasements rendered waterproof, thus attaining immunity from water, moisture, fire, etc., and adapting .my system particularly to the requirements or police and the department signal stations, subways, mining operations, etc.

For this reason also the contact points may be protected from corrosion, and from lodgment of dust between the points, resulting heretofore in imperfect electrical contact and partial or complete opening of circuit, thus impairing utility and service. Furthermore, by my method of mounting the induction coil within the casing of the desk telephone, I obviate the necessity for a third electric conductor in the cord which unites the desk cord with the ringer and condenser box, two electric conductors only being required to do the work of three as in installations heretofore. I am also thus enabled to use a rubber-covered twisted pair of flexible wire cords which will resist water and moisture, thus rendering the telephone immune from short circuits in this respect. The fact that the induction coil is mounted on the frame ofthe desk phone also permits connections to be made permanently to the said coil; and only a sin le contact point is required on the switch ior signalling purposes, thereby reducing to a minimum the chances of ineficiency. Another advantage attained by my system of installation is that the wall telephone requires no extraneous cord except the receiver cord, as the receiver, transmitter, and induction coil are mounted, in the same. box with the rinfger and condenser.

t will thus 'be seen that by my invention I am enabled to dispense with a number of parts and devices heretofore used in telephone installation, and to greatly simplify and reduce not only the initial cost of such installation but also the cost of maintenance. By reducing the number of contacts In, is, to a minimum, I eliminate several rubber bushings, such bushings being fragile and liable to deteriorate and break, resulting in short circuiting, etc.

By my improved method or connecting up the circuits in a telephone systemthe telephones will render better service and will be less prone to get out of order. The transmission will be greatly improved and will render better service to the public in general. My telephones are intended to operate normally on a circuit of twenty to twenty-five volts produced by storage or secondary batteries, or dry or wet primary batteries. These telephones will also operate on a circuit of six to ten volts produced by the same means as the twenty to twentyfive volt circuit, but it is not intended to use so low a voltage to get the best results in telephone service.

menses What I claim as m invention and desire to secure by Letters atent is,

1. Inatelephone installation embodyinga central energy system the combination of winding of high resistance, said transmitter and the primary winding of said induction coil being in series with each other but in parallel with the secondary winding with reference to said line wires.

2. In a telephone installation embodying a central energy system the combination of a pair of line wires, a receiver, a single pair of closure contact members controllable by the weight of said receiver, a transmitter, and an induction coil provided with a primary winding of low resistance and with a secondary winding of high resistance, said pair of closure contact members and said receiver being in series with each other and with the line wires, said secondary Winding being in parallel with said primary winding and said transmitter with reference to the line wires.

3. In a telehone installation employing a central energy system, the combination of a pair of line wires, a sin le pair of contact members and a telep one receiver in series with said line wires, said contact members being controllable by the Weight of said receiver for o ening and closing the line, an induction coi provided with a primary winding and with a secondary winding, and a transmitter in series with said primary winding, said transmitter and said. primary winding being in parallel withsaid secondary winding with reference to said line wires and to said contact members and said receiver.

4. In a telephone installation of the character described, the combination of a ver' tically extending supporting member to be mounted within the casing of adesk telephone receiver, a single pair of closure contact members mounted upon said supporting member and controllable by the weight of said receiver, an induction coil mounted upon said supporting member and provided with a primary winding and a secondary winding, a connection from said primary winding and said secondary winding to said receiver, a connection from said receiver to one of said contact membersa line wire connected with the other of said contact members, a transmitter connected with said primary winding, and another line wire connected with said transmitter and with said secondary winding.

EDWARD A. DRISCOLL.

Witnesses:

GEO. WM. Mia'r'r, DOROTHY Mmr'r. 

